Various types of ink-jet printers are known in the art. In these types of printers, maximum printing areas are defined for individual standard sizes of recording media. In general, the maximum printing area is defined in terms of top-, bottom-, right- and left-margins so that the printing area is smaller than the size of a recording medium by the amount defined by the margins. Each margin is set to a value in the range from 3 mm to 13 mm, and no printer has been proposed which can perform a printing operation in an area including the end portion of the recording medium.
Furthermore, in another known small-sized ink-jet printer, a tape having a color selected from various colors can be employed as the recording medium, and color printing can be performed onto the selected tape. In the small-sized ink-jet printer of this type, a color printing operation is performed onto a tape with inks supplied to ink-jet print heads from ink tanks for color inks of cyan (C), magenta (M), and yellow (Y).
As for the tape, it is known to provide a tape which has a releasable sheet covering the back surface of the tape via an adhesive layer. After completion of printing, the tape is cut into a piece having a proper size. Then the releasable sheet is removed and the tape is affixed to a desired object. The printer of the type designed to perform a printing operation onto this type of tape is called a label printer or label word processor and is now popular in the market.
However, when the conventional ink-jet printer is used to perform a solid printing operation across the entire area of a recording medium such as a tape, there occurs a problem in that a non-printed area is produced at an end portion of the width of the tape.
To perform a solid printing operation by moving a print head in a reciprocating fashion across the width of a tape without producing a non-printed area at the edges of the tape, it is required to start a printing operation at one end of the width of the tape and stop the printing operation at the other end of the width of the tape.
However, it is generally difficult to precisely drive the print head so that the printing operation is started precisely at one edge of the width of the tape and is stopped precisely at the other edge of the width of the tape. This difficulty arises from a slight deviation in the tape carrying position in a direction across the width of the tape, or from a timing error between the ink ejection operation and the reciprocating movement of the print head.
If the printing operation is not controlled precisely, a non-printed area is produced at a region near the edge of the width. This could occur, for example, if the start of the printing operation is delayed from the time at which the print head is at the edge of the width of the tape.
In view of the above, it is an object of the present invention to provide an ink-jet printer capable of performing a printing operation for a limited area at an edge of the width or the entire area of the tape without producing a non-printed part in the selected area, or across the entire width or along the entire length of the tape without producing a non-printed part in the selected direction (hereafter, these printing operation modes are represented by a generic term "solid printing mode").
Furthermore, it is another object of the present invention to provide an ink-jet printer that does not make a recording medium dirty with ink droplets which are deposited on a guide element or the like during a solid printing operation.
It is a further object of the present invention to provide a recording medium suitable for use with an ink-jet printer capable of performing a solid printing operation.
To achieve the above objects, the present invention provides an ink-jet printer in which a print head is controlled so as to make possible performing a printing operation in an area which is deviated outward from the leading or trailing edge or either side of a recording medium such as a tape being carried (this printing operation will also be referred to as a "passing-over" printing operation). With this arrangement, the print head is driven in such a manner that the printing operation is performed continuously until the print head has moved past the edge of the width of the length of the recording medium thereby accomplishing the solid printing operation without producing a non-printed area at the end portion of the recording medium.
Furthermore, in addition to the above construction, the ink-jet printer of the present invention also has excess ink capturing means for capturing the ink droplets which are ejected from the print head when the print head is at a passing-over position. According to this technique, it is possible to avoid the deposit of the ejected ink droplets onto the guide element disposed facing the print head and thus it is possible to prevent the following recording medium from being dirtied with the deposited ink.
More specifically, according to an aspect of the present invention, there is provided an ink-jet printer comprising: a recording medium supplying source; a carrying path along which a recording medium supplied from the recording medium supplying source is carried; recording medium carrying means for carrying the recording medium along the carrying path; an ink-jet print head disposed on the carrying path, the ink-jet print head being adapted to move in a reciprocating fashion along a first direction relative to the recording medium to be carried; ink supplying means for supplying ink to the print head; and printing operation control means having the capability of setting the printing range of the print head in the first direction so that the printing range includes a region outside the edge of the recording medium.
In the above-described ink-jet printer, the printing range in the first direction, that is the range in which a solid printing operation is possible, is for example a direction across the width of the recording medium perpendicular to the carrying direction along which the recording medium is carried. Alternatively, the first direction may be a direction along the length of the recording medium parallel to the carrying direction along which the recording medium is carried. Furthermore, it is also possible to set the printing range in such a manner that, in addition to the first direction, the printing range also includes an area which is deviated outward from an edge of the recording medium in a second direction different from the above first direction. For example, if the first and second directions are selected so that they are perpendicular to each other, it is possible to accomplish a solid printing operation over the entire area of a recording medium.
In another aspect of the invention, the ink-jet printer further includes excess ink capturing means for capturing the ink droplets which are ejected from the print head when the print head is located at a position deviated outward from the edge of the recording medium.
The above-described excess ink capturing means is disposed at a location facing the printing head via the carrying path, and the excess ink capturing means is formed over the entire range including the printing range of the print head, wherein the printing range includes an area outside the edge of the recording medium. To achieve such a construction, the excess ink capturing means is disposed on a guide element which defines the position of printing performed by the print head onto the recording medium being carried. In this case, the surface of the guide element facing the recording medium can be formed of a stainless steel mesh.
Furthermore, it is desirable that the excess ink capturing means include ink exhausting means for exhausting captured ink thereby preventing the excess ink capturing means from becoming full of the captured ink and thus maintaining the capability of capturing excess ink droplets.
In the case of an ink-jet printer for performing a printing operation onto a large-size recording media, it is not economical to dispose the excess ink capturing means across the entire width or along the entire length. The above problem can be avoided if the excess ink capturing means is adapted to move in one piece with the print head. This construction may also be applied to a small-size recording medium.
A tape having a great length and having a constant width can be employed as the recording medium. In this case, a tape cartridge can be employed as the recording medium supplying source in which the tape, wound in the form of a roll, is accommodated wherein the tape cartridge is adapted to be removably mounted in the main part of the ink-jet printer.
In this case, the tape cartridge can accommodate various tapes having different widths. Therefore, to make it possible to correctly set the printing range of the solid printing operation corresponding to the width of a tape used, the tape cartridge further includes width indication means for indicating the width of the tape accommodated in the tape cartridge; the printing operation control means includes reading means for reading the width indicated by the width indication means; and the printing range of the print head in the first direction is set according to the width read by the reading means so that the printing range includes an area outside the edge of the recording medium.
Furthermore, a transparent medium such as a transparent tape may be employed as the recording medium.